Subang among top lightning-prone spots in the world

Kuala Lumpur: Subang which lies in the centre of a lightning dense triangle in the Meteorological Department’s map for lightning density has one of the highest number of lightning incidences in the world.

According to the department, Subang experiences lightning a minimum of 240 days a year.

This translates to between 25 and 40 lightning ground flashes per sq km in the area a year.

Subang resident Teoh Teik Hoong, who runs the community paper SJ Echo, said having his house tripped by lightning and seeing streaks of lightning across the sky was common.

“We remind our youngsters that lightning is dangerous and its frequent here. There were cases of young boys struck by lightning in football fields, this made the community very sensitive to this,” he said.

Teoh said Subang Jaya state assemblyman Hannah Yeoh often reminds people to keep their children indoors when it starts to pour.

“I make it a policy for my boys. If you see dark clouds, it’s time to get home. This is always a constant reminder,” he said.

The reason for the area’s proclivity to lightning, said the Meteoro­logical Department, was its location in a low lying, flat Klang Valley and its concentration of concrete buildings and roads.

“With such conditions, strong heating on the surface air tends to occur, which leads to convection activities in the atmosphere. As a result, convective or thunderstorm clouds will form followed by lightning,” it said.

Universiti Putra Malaysia electrical engineering professor Dr Chandima Gomes said the Klang Valley records the highest number of lightning in May and October, during the intermonsoon period.

In those months, the Malacca Straits experiences hot weather which evaporates water and pushes hot air to cooler areas in the Klang Valley.

These water molecules rise up until they form ice crystals and clouds which result in lightning.

Dr Chandima said Venezuela and the Congo Basin have more lightning than Malaysia but those areas were generally unpopulated.
“For lightning impact, we are number one. Because there are just so many people and buildings in the Klang Valley and Subang,” he said.

Meanwhile, Malaysia have just crossed the year’s lightning month with an average 86,000 strikes recorded in peninsula alone.

With the monsoon season and more lightning expected this month, experts renewed their calls for better lightning protection.

The Klang Valley receives the third highest number of lightning strikes in the world.

Scientists consider it the “lightning crown of the world” because it is the most populated and developed of the top three.

The Fire and Rescue Department does not keep records of fires caused by lightning and neither do the Urban Wellbeing, Housing and Local Government or KL City Hall have policies on lightning proofing buildings in their jurisdiction.

A study by Universiti Putra Malaysia found that Malaysians list severe weather, including lightning, as a top concern but believed lightning strikes was something “you can’t protect yourself from”.

“It’s very sad. Even engineers don’t know this,” he said.

In 2011, the Government issued a circular for buildings to adopt an international standard for lightning protection called MS IEC 62305, but Dr Mohd Zainal said this standard was rarely enforced.

This has led to developers and building managements having complete control on what kind of lightning protection they want to have for their structures.

One of the most popular forms of lightning protection here, he said, was installing Early Streamer Lightning Protection – a metal rod that stands on a roof and is claimed to be able to attract lightning and ground it safely.

However, this claim has never been backed by international research but has caught on here because it is cheap and widely used by contractors.

Dr Mohd Zainal also said that even when proper Franklin rods and grounding systems were used, they were often installed at the wrong places – like the middle of the roof instead of at all the roof corners.

“Some only have one rod covering the whole building, without any consideration to the size of the building or of its architecture.”

This has led to dangerous and costly consequences.

In 2006, lightning ignited 720,00 litres of fuel at the Johor Port in Pasir Gudang. In 2011, fire destroyed three wards of the Putrajaya Hospital after it was struck.

As recently as last year, a man in Ipoh was electrocuted to death in his shower after lightning fried his home’s fuse box and water heater.

“There really isn’t any clear authority or consistent approach for lightning protection here. The MS IEC standard isn’t tied to any law and jurisdiction between Federal and local government makes it hard to implement,” he said.

The Energy Commission (ST) is currently conducting a study to gauge the extent of the Klang Valley’s preparedness for lightning, though Dr Mohd Zainal believed that more than 90pc of our buildings were not protected.